Aerodynamic shells, also called aeroshells or fairings, can be used in an effort to present a more aerodynamic airfoil profile for sections of wind turbine blades. International Patent Application Publication WO 2013/092852 shows a wind turbine blade assembly wherein a blade part is mounted on a cylindrical blade extender part, with an aeroshell used to effectively convert the cylindrical extender into a blade portion having an airfoil profile.
However, while the use of such aeroshells can improve aerodynamic performance of a wind turbine blade section, they can also introduce additional complications with regard to the distribution of stresses and strains in the general wind turbine blade structure. In particular, the extended trailing edge formed by the end of the aeroshell section is regularly subjected to relatively high stress levels during wind turbine operation. Accordingly, increased levels of reinforcement material are required to prevent failure of the aeroshell, which increases the eventual weight and cost of wind turbine blades utilising such aeroshells.
WO 2011/157849 discloses a blade provided with a pre-manufactured trailing edge part for an outboard part of the blade. In one embodiment, the pre-manufactured part is provided with channels formed in the surface of the part having a depth of 0 to 10 mm with the purpose of minimising noise.
EP 1 338 793 discloses a blade provided with trailing edge serrations at an outboard part of the blade in order to minimise noise emissions.
WO 2010/043647 discloses a blade provided with a number of trailing edge sections, such as trailing edge flaps, along an outboard part of the blade, and which are individually controllable.
It is an object of the invention to provide an aeroshell construction which is relatively flexible, and which is arranged to better withstand operational stresses and strains when installed as part of a wind turbine blade construction.